Make the topping: In a small bowl with your fingertips blend butter, brown sugar, and flour until smooth and blend in nuts. Chill topping, covered.

Make the filling: Peel and core apples. Cut apples into 1/2-inch wedges and in a bowl toss with remaining filling ingredients to coat.

Preheat oven to 350 degrees. Spoon filling into unbaked shell. Bake pie in middle of oven for 1 hour (pie will not be completely cooked) and remove from oven.

Crumble topping over center of pie, breaking up any large chunks. Brush crust with milk and sprinkle with sugar. Bake pie in middle of oven 30 minutes more, or until crust is golden and filling is bubbling. Cool pie on a rack. Serve pie warm or at room temperature with ice cream.